Rachel Bilson Cheers on 'The O.C.' Co-Star Mischa Barton During 'DWTS'!

Mischa Barton is led by her partner Artem Chigvintsev while dancing in the Dancing With the Stars premiere on Monday night (March 21) in Hollywood.

The duo performed the Tango and received 16 out of 30 points from the judges.

PHOTOS: Check out the latest pics of Mischa Barton

In case you missed it, watch Mischa and Artem‘s week one dance now!

Mischa‘s former O.C. co-star Rachel Bilson took to Instagram to support her.

“Got to give it up for @mischamazing takes balls. Get it guurrrrlll!” Rachel captioned a photo of her television.